User Manual

Commissioning
SmartRadar FlexLine Part No.: 4417.762_Rev07
6 - 72 Service Manual
6.5.2.5 Alarm Loop Checking
Normally, level alarms can be verified when the level reaches the low-
level or high-level alarm set point. The level alarms and, if applicable,
the hard alarm contact coupled to one of the level alarms can be
checked by a “loop check” command. This check is independent from
the actual level value.
The level alarm signalling can be checked in several ways:
 via the communication line to the host
 via the hard alarm output contact
☛ To perform the alarm test, set
[Alarm test enable] to <Enable> and set
[Alarm test] to the required alarm (<High High alarm>, <High Alarm>, <Low
Alarm>
, or <Low Low alarm>). [Alarm test] is a parameter command, and
the command will be executed when the parameter is sent to the
gauge. When the command is given, the corresponding alarm will be
set for 1 minute.
6.5.2.6 Compensations
6.5.2.6.1 Filtering
The gauge contains an output filter for both radar innage and radar
ullage. The higher the
[Filter averaging constant], the more damping on the
radar innage and radar ullage values. The filter also introduces a lag
between actual ullage/innage and filtered ullage/innage when the
product level is changing. The higher the
[Filter averaging constant], the
larger the lag. The minimum
[Filter averaging constant] value is 0 (no
filtering), the maximum
[Filter averaging constant] value is 99. For the
general filter behavior, see FIGURE 6-11.
FIGURE 6-11 Filtering characteristic example (level change = 5 mm/s)
5.3
5.25
5.2
5.15
5.1
5.05
5.0
4.95
0 20406080100120
Filtering averaging constant = 98
Ullage
Average
Ullage [m]
Time [s]
Exponentially weighted moving average filter
maximum lag [m]
maximum lag [s]